Dear Asif,
I am assuming that you have Original car registration book. Visit the office where you get registered your car and take maximum information about your car custom clearance certificate and other important data like date, bill of lading etc.
Now follow steps which I am mentioning;
1. Report to Police station of your respective area,for lost of your car file somewhere.
2. Put an Ad in express news, it is cheaper than others. 3. After Ad publishing, purchase two sets of newspapers.
3. A 100 or 200 stamp paper for Custom Deputy Collector about your matter.
4. Take the samples of newspaper ad and stamp paper letter from NLC custom office Thokar Niaz Baig, Lahore.
5. Meet importer to know where the car custom duty was paid, Lahore, Karachi etc?.
6. If Lahore, visit NLC Custom Office at Thokar Niaz, meet the officials and clerk. Submit the documents like police report, ad original, CNIC copy, Stamp paper etc.
7. If Karachi, then request NLC office Lahore to let you confirm on which port your car was landed and got custom clearance. North or West Port... Bin Qasim Port i think.
8. Visit there for the same process.
9. Expense charges are approx. 35k. These charges are without hiring any agent but you have to spend this amount on ............. I think you understand what i mean.
Hope you understand the procedure